SI units

Definition

SI units (International System of Units) are the standard units of measurement used globally in science and industry. They ensure consistency and accuracy in the representation of physical quantities.

5 Must Know Facts For Your Next Test

1. SI units are based on seven base units: meter (m), kilogram (kg), second (s), ampere (A), kelvin (K), mole (mol), and candela (cd).
2. The SI system is maintained by the International Bureau of Weights and Measures (BIPM).
3. Derived units are formed from the base units, such as newton (N) for force and joule (J) for energy.
4. SI prefixes like kilo-, milli-, and micro- denote multiples or submultiples of units.
5. The SI unit for temperature is kelvin, which is crucial for studying thermodynamics.

Review Questions

• What are the seven base SI units?
• How do you form derived units in the SI system?
• What is the significance of using SI prefixes?

Related terms

Base Units: The fundamental units in the SI system from which all other units are derived, including meter, kilogram, second, ampere, kelvin, mole, and candela.

Derived Units:

Units that are formed by combining base units according to algebraic relationships; examples include newton for force and joule for energy.

Prefixes: Standardized additions to unit names that indicate decimal multiples or fractions of a unit, such as kilo- ($10^3$) or milli- ($10^{-3}$).